The conversion by refining industries of light paraffins and light olefins to more valuable cuts has been accomplished by the alkylation of paraffins with olefins and by the polymerization of olefins. Such processes, which have been used since the 1940's, continue to be driven by the increasing demand for high quality and dean burning high-octane gasoline, distillate, and lubricating base oil.
Conventional alkylation processes use vast quantities of H2SO4 or HF as catalyst. The quest for an alternative catalytic system to replace the conventional catalysts has been researched by various groups in both academic and industrial institutions. Thus far, no viable replacement to the conventional processes has been commercialized.
Recently there has been considerable interest in metal halide ionic liquid catalysts as alternatives to conventional catalysts. As an example, the ionic liquid catalyzed alkylation of isoparaffins with olefins is disclosed in U.S. Pat. No. 7,432,408 to Timken, et al. Further, U.S. Pat. No. 7,572,943 to Elomari, et al. discloses the ionic liquid catalyzed oligomerization of olefins and the alkylation of the resulting oligomers(s) with isoparaffins to produce alkylated olefin oligomers.
The presence of HCl as a co-catalyst with an ionic liquid provides an increased level of catalytic activity, for example, as disclosed by the U.S. Pat. No. 7,432,408 patent. Typically, anhydrous HCl or an organic chloride co-catalyst may be combined with the ionic liquid catalyst to attain the desired level of catalytic activity and selectivity (see, e.g., U.S. Pat. No. 7,495,144 to Elomari and U.S. Pat. No. 7,531,707 to Harris, at al.). When organic chloride is used as co-catalyst with the ionic liquid, HCl may be formed in situ in the reactor during the hydrocarbon conversion process.
Hydrocarbon product(s) of ionic liquid catalyzed hydrocarbon conversions, such as alkylate or distillate or base oil, typically contain substantial amounts of is organic chloride components that are produced during the reaction. In addition, organic chloride co-catalyst may also be carried over into such hydrocarbon products. The removal of organic chloride components from the hydrocarbon products may be desirable, e.g., to prevent the formation of unwanted byproducts during combustion of liquid fuels (see, for example, U.S. Pat. No. 7,538,256 to Driver, et al., and U.S. Patent Application No. 2009/0163750 A1 (Timken, et al.)).
U.S. Pat. No. 5,107,061 to Ou, et al, discloses the removal of organochlorines from hydrocarbon streams containing olefinic compounds using an adsorbent comprising a molecular sieve in combination with alumina to form an unsaturated hydrocarbon molecule and a molecule of hydrogen chloride, wherein the hydrogen chloride is adsorbed by the adsorbent.
There is a need for processes for the efficient dechlorination of hydrocarbon products derived from ionic liquid catalyzed hydrocarbon conversion reactions.